Common structures of Rigid-flex PCB
- The rigid flex board is to glue one or more rigid layers on the flexible board. The circuit on the rigid and flexible layersare connected through metallization. Each rigid-flex board has one or more rigid areas and a flexible zone
- The combination of one flexible board and several rigid boards, and the combination of several flexible boards and several rigid boards,
The electrical interconnection is realized by drilling, plating holes, and laminating processes. According to the design requirements, the design concept is more suitable for installing and debugging the device and the welding operation. The installation of the assembly is more flexible.
Design Suggestions of Rigid-flex PCB
Rigid flex PCB board is a product segmentation that promotes technical level and application field of flexible circuit boards to help system products move to a broader space. Not only can the product be more miniaturized, but it also can solve many problems in assembly and wiring.
Structural considerations are the most critical factor in the design of Rigid-flex. It is necessary to make the process simple, highly reliable, and achieve low cost and application.
1.The thickness should be reduced as much as possible, and the types of materials must also be reduced.
Rigid Flex PCB that is too thick adversely affects the miniaturization of assembled thick products. It also causes inconvenience to the manufacturing process, especially pressing. In addition, the types of materials used by Rigid-Flex include copper foil, polyimide film, and acrylic glue. Different materials, such as different materials, will cause considerable challenges in dimensional accuracy. Simultaneously, due to the large difference in thermal expansion coefficient, the adhesion between the layers after thermal shock also needs attention.
2.Stress prevention at bending points
In addition to the process of hot pressing, it is necessary to reduce the stress on the contact edge of the flex and rigid board or provide additional reinforcement. The best policy is to avoid bending points.
- Consideration of folding resistance and shock resistance. Wiring deployment must meet folding resistance. Prior consideration is needed if the product is being used in a high-vibration environment.
- Process considerations Pre-imagine the problems that may occur in the process, simplify the process to reduce costs and increase yield